The primary objective of this research is the development of a sensitive radioimmunoassay (RIA) for the detection of human melanoma tumor associated antigens (TAA). This assay would be useful for monitoring the course of melanoma patients undergoing various forms of therapy and for the investigation of the roles of soluble TAA and TAA-antibody complexes in the disease process. Operationally monospecific alloantisera and autoantisera from melanoma patients and chimpanzee, monkey and rabbit heteroantisera against melanoma TAA are being employed to isolate pronase-solubilized melanoma TAA and serum-borne TAA. These, in turn, will be used to produce highly specific heteroantisera for use in the RIA. Serum and urine of melanoma patients will be compared to those of control donors to validate the RIA. In vitro and in vivo antibody localization procedures are also being developed using autoradiography and immunofluorescence. Human melanomas growing in nude mice and the B16 melanoma of C57BL/6 mice are being used as animal models to further these studies. Passive serotherapy will then be attempted in these models. The antimelanoma antisera will also be used for solid tumor immunodiagnosis where diagnosis cannot be made using conventional pathology techniques.